fix(overlay): fix macOS overlay interactivity and focus after autoplay (#106)

src/main/runtime/macos-overlay-window-focus.ts

@@ -0,0 +1,54 @@
+type FocusableOverlayWebContents = {
+  isFocused: () => boolean;
+  focus: () => void;
+};
+
+type FocusableOverlayWindow = {
+  isDestroyed: () => boolean;
+  isVisible: () => boolean;
+  isFocused: () => boolean;
+  setFocusable?: (focusable: boolean) => void;
+  focus: () => void;
+  webContents: FocusableOverlayWebContents;
+};
+
+export type MacOSOverlayWindowFocusDeps = {
+  platform: NodeJS.Platform;
+  getOverlayWindow: () => FocusableOverlayWindow | null;
+  stealAppFocus: () => void;
+  warn: (message: string, details?: unknown) => void;
+};
+
+// macOS only delivers mouse-moved/hover events to the key window of the frontmost application.
+// After autoplay warmup completes mpv is the frontmost process, so the transparent overlay window
+// receives no pointer events until the user physically clicks a subtitle (which activates the app
+// via acceptFirstMouse). Renderer-side pointer recovery can toggle setIgnoreMouseEvents but cannot
+// make the window key, so it cannot wake hover on its own. Activating the overlay window from the
+// main process reproduces that manual click and keeps subtitles interactive.
+// (Modal close takes the opposite path — see restoreMacOSMpvFocusAfterModalClose — because the user
+// needs keyboard focus back on mpv, with the overlay floating passively above it.)
+export function focusMacOSOverlayWindow(deps: MacOSOverlayWindowFocusDeps): void {
+  if (deps.platform !== 'darwin') {
+    return;
+  }
+
+  const overlayWindow = deps.getOverlayWindow();
+  if (!overlayWindow || overlayWindow.isDestroyed() || !overlayWindow.isVisible()) {
+    return;
+  }
+  if (overlayWindow.isFocused()) {
+    return;
+  }
+
+  try {
+    deps.stealAppFocus();
+  } catch (error) {
+    deps.warn('Failed to steal app focus for overlay window', error);
+  }
+
+  overlayWindow.setFocusable?.(true);
+  overlayWindow.focus();
+  if (!overlayWindow.webContents.isFocused()) {
+    overlayWindow.webContents.focus();
+  }
+}